Gas boiler



Nov. 6, 1928. H 1,690,105

E. R. DOWNE GAS BOILER Filed Sept. 30. 1925 3 Sheets-Sheet 1 INVENTOR mATTORNEY Nov. 6, 1928.

E. R. DOWNE GAS BOILER Filed Sept. 50, 1925 3 Sheets-Sheet INVENTOR :1.vMlumzf ATTORNEY E. R. DOWNE GAS BOILER 3 Sheets-Sheet 3 Filed Sept.30-, 1925 QNN I IIH 1| I l I 15 ML W. BY "Gm/(1Z ATTORNEY u l 3 mmPatented Nov. 6, 1928.

UNITED STATES PATENT OFFICE.

EDWARD B. DOWNE, OI LARCHMONT, NEW YORK, ASSIGNOEB. 'IO AMERICANRADIATOR COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEWJERSEY.

ens BOILER.

Application filed September 30, 1925. Serial No. 59,442.

My invention relates to improvements in heating apparatus, and the samehas for its object more particularly to provide a simple, efficient andreliable boiler in which the water or other medium circulating throughthe same is heated by the hot gases and products of combustion resultingfrom the burning of a gaseous or other fuel.

Further, said invention has for its object 1 to provide a boiler inwhich a relatively large amount of the heat resulting from the com-,

bustion of said fuel is efliciently absorbed by the water or othercirculating medium in the boiler.

Further, said invention has for its object to provide a boiler in whichthe heat absorbing surfaces thereof are such as to efficiently transferto the circulating medium of the boiler the maximum amount of heat saidcirculating medium is capable of acquiring or absorbing.

Further, said invention has for its object to provide .a boiler having aminimum of heat absorbing surfaces in intimate contact with the hotgases and products of combustion passing through the flues of the boilerat high velocity, andin which said heat absorbing surfaces efficientlytransfer the heat acquired thereby to the circulating medlum Within theboiler.

Further, said invention has for its object to provide a boiler in whicha large number of relatively small projections or heat absorbingelements are distributed over the Walls of the flue or flues thereof invertically staggered relation and extend into the pat of the hot gasesand products of combustion passing through the flue at high velocity inintimate and effective contact therewith.

Further, said invent-ion has for its object to provide a boiler in whichthe sections thereof may be readily assembled to form the flues withoutthe heat absorbin elements or projections interfering with t e properalinement and registry of said sections.

Further, said invention has for its object to provide a boiler in whichthe hot gases and products of combustion as the same enter the flue orflues are subjected to Venturi-like of combustion to spread or fan outlaterally before the sameengage with'the projections or heat absorbingelements throughout the entire area of the flue.

action to cause saidgases and said products Further, said invention hasfor its object to provide a boiler in which the transverse flue areathereof is greater at the inlet than at the outlet of the flue, and inwhich the free upwardly in transverse area in accordance with thedecrease in temperature of the gases and products of combustion as thesame pass towards the outlet of the flue.

Further, said invention has for its object to provide a boiler in whichthe projections or heat absorbing elements extending into the path ofthe hot gases and products of combustion passing through the fluesprovide with the walls of the flue an extended surface area soproportioned as to abstract from the hot gases and products of combustion substantially the maximum amount of heat capable of being absorbedby the circulating medium within the boiler and to transfer the samethereto and in which said projections or heat absorbing elements are sospaced as to permit of the said hot gases and products of combustionpassing through said flues at relatively high velocity.

Further, said invention has for its object to provide a boiler in whichrelatively small, solid, heat absorbing rojections or elements aredistributed in en cient numbers over the walls of the flue to provide arelativel large area between the same sufiiciently large to permit ofthe hot gases and products of combustion passing through, the flue atrelatively high velocity.

Further, said invention has for its object to provide a boiler in whichthe relatively small, solid rojections are arranged in rows upon the wals of-the flue or flues to provide spaces between adjacent rows adaptedto receive an instrument to permit of the entire. surface of saidprojections being cleaned.v

Further, said invention has for its object to provide a'boiler in whicha plurality of relatively small rojections are distributed over thewalls 0 the flue and extend into the ath of the hot gases and'productsof- .com ustion passing therethrough, and in which the dimensions ofeach of said projections are such as to permit of the propertransmission therethrough to the circulating medium of the heat absorbedby said projections.

Further, said invention has for its object to provide a boiler in whicha large number of relatively small projections orhcat absorbing elementsare disposed upon the walls of the flue or flues and extend into thepath of the hot gases and products of combustion passing therethrough,and in which the length of each projection is less than or not greaterthan twice the average diameter thereof.

Further, said invention has for its object to provide a boiler of thecharacter specified which shall be compact in form, and occupy about onehalf of the volume ordinarily occupied by solid fuel burning boilerspossessing I the same rating.

Other objects will in part be obvious, and in part be pointed outhereinafter.

To the attainment of the aforesaid objects and ends, my inventionconsists in the novel details of construction, and in the combination,connection and arrangement of parts hereinafter more fully described andthen pointed out in the claims.

In the accompanying drawings showing an illustrative embodiment of theinvention-- Figure l is a front elevation showing one form of boilerconstructed according to and embodying my said invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a vertical section on the line 3-3 of Fig. 4;

Fig. 4 is a vertical section thereof on the line 14.ofFi .3;

5 is an elevation of one face of a boiler section;

Fig. 6, is a vertical section thereof on the line 66 of Fig. 5;

Fig. 7 is an enlarged detail face view showing the arrangement of theheat absorbing elements or pro ections shown at-Fig. 5; and,

Fig. 8 is an enlarged detail sectional view taken on the line 88 of Fig.7.

Referring to the drawings, the boiler 10 comprises hollow end sections11 and 12, and a plurality of hollow intermediate sections 13. T 1e endsections 11 and 12 extend downwardly below the intermediate sections 13to provide pedestals or supports 14 on which the boiler rests and toprovide a; combustion chamber 15 below the sections 13. In thecombustion chamber 15 is located suitable heating means, such as gasburners 16.

The sections 11,12 and 13 are provided with three series of alinedopenings 17, 17 and 17 within which are secured the nipples 18 in orderto hold said sections in assembled relation, and to permit of thecirculation of heating fluid throughout the boiler.

The series of openings 17 and 17 are arranged at the bottom at oppositesides of the at the front to permit access to the combustion chamber 15,and said opening 20 is closed "by a suitable frame or closure 21 throughwhich the gas pipes or burner tubes 22 to the burner 16 and the pilotline 23 pass. The burner tubes 22 and pilot light 23 are supplied withgas from the manifold 24 which is controlled by a suitable gas governorE25, and by a snap valve 26 adapted to be actuated through theconnections 27 by the usual thermostatic or pressure responsiveregulator. The frame 21 has sight openings 28 therein. Bafile plates 29are disposed horizontally between the pedestals 14 at the front and rearof the burners 16.

Above the combustion chamber 15 the successive sections are in spacedrelation to each other to provide between them a plurality of verticallines 30 through which the hot gases and products of combustion from thecombus tion chamber may pass and contact with the heat absorbingsurfaces of the sections to heat the water therein. The lines 30 areopen at the top and dischar e the gases or products of combustion into ac iamber or smoke hood 31 having a stack or outlet 32.

T he several sections are maintained in spaced relation to form saidtimes 30 by means of the integral marginal flanges 33 and the hubs ornipple ports 34 and 34" registering with each other at their opposingedges.

Distributed over the opposing walls of the fines 30 are a. plurality ofhorizontal rows 35 of relatively small tapering projections or heatabsorbing elements 36. The projections are preferably cast integrallywith the sections upon both sides of the section 13 and upon one side ofthe sections 11 and 12, and said projections are substantially solid.

The projections 36 are slightly shorter than the Width of the marginalflanges 33 to permit of the sections being evenly engaged at the marginsand at the ends of the hubs 34 and 34. Each row of projections 36 isarranged in horizontal alinement with a correspondin row upon theopposing wall of the flue 30, and

the corresponding opposing projections are spaced at their adjacentends, as indicated at 3 whereby the entire surface of each projection isexposed to the hot gases and products of combustion passing through theflues 30. The projections 36 of each row are also staggered relative tothe projections of the adjacent rows above and below the same. Theflanges 33 are interrupted at one side of the boiler to provide anopening 38 to each flue through which a suitable instrument or brush maybe inserted into the horizontal spaces 39 between the rows 35 forcleaning the projections 36. As these projections have very smalldiameters substantially the entire exposed surface thereof may bereadily cleaned y the operation. The openings 38 are normally closed bysuitable closures or covers 40, (Fig. 5) and secured in position byscrews 40a and a thumb nut 40". Each screw 40 has a hook 40 at its innerend engaging certain of the projections 36 on the boiler sectlons 13.

The number of projections 36 extending into the ath of the hot gases andproducts of combustion is sufliciently large to permit of saidprojections and. the walls of said flue absor ing from the said gasesand products of combustion, and transmitting to the circulating mediumthe maximum amount of heat which the circulating medium or water withinthe boiler is capable of absorbing.

In the boiler embodying my said invention a relativel large heatabsorbing area per unit of water acked surface is provided, in order toinsure the absorption by the circulating medium of the maximum amount ofheat, without unduly restricting the free transverse flue area betweenthe projections, and, thus permit the hot gases and products ofcombustion to pass through said flues at a high velocity in intimate andeffective contact with the heat absorbing surfaces thereof. The resultis obtained by providing a large number of very small projections 36 anddisposing the same upon the opposin walls of the flue witl1- out undulyretarding t e flow of the hot gases and products of combustion. Inpractice, the

length of each projection 36 should not exceed twice the averagediameter thereof to insure the proper transmision of heat from the hotgases through the projection to the water or circulating medium withinthe boiler. The cross sectional area of the projection at the basethereof, which represents the metal through which the heat has to betransferred, is approximately one fourth of the area of the totalexternal or exposed surface of said projection. In order to effect theeflicient trans fer of heat from the hot gases to the circulatingmedium, the projections of each horizontal row 35 should preferably bespaced from each other a distance equal to or slightly exceeding themaximum diameter of the individual projection. The construction andarrangement of the'projections 36, as hereindescribed, serves to divideeach flue into a series of uninterrupted vertical passages 36*, each ofwhose area in cross-section is relative- 1y wide at its intermediateportion 36", and tapers towards the opposite ends 36 thereof, as shownat Figs. 7 and 8.

The inner adjacent curved surfaces 41 of the hubs 34 form a constrictedinlet to each flue,

providing a Venturi-like entrance portion which causes the, hot gasesand products of each flue 30 is wider than the upper portion thereof toprovide a transverse flue area at the entrance or inlet thereof ample topermit of the passage of all of the highly heated gases and products ofcombustion into the flue. The outlet 43 of the flue, restricted by thehubs 34', has a transverse flue area less than that of said inlet 42.The free intermediate flue area between the heat absorbing projections36 is less than the corresponding area at the inlet and greater than thecorresponding area atthe outlet of the flue, the transverse flue areadiminishing in accordance with the decrease in temperature of the gasesand products of combustion as the same pass towards said outlets 43.

In operation the gases pass at high velocity through the flue 30 in finestreams in intimate contact with the projections 36 and the walls .ofthe flues. B the time said gases reach the top of the boi er the maximumamount of heat has been abstracted therefrom and transferred to theWater or circulating medium.

In actual use of a boiler embodying the invention it has beenascertained that the gases entering the flues with a temperature ofabout 2000 F. and after passing through said flues to the outletsurrendered about 1700 F. of heat during the travel through said fluesconsuming about 1/6 second, and indicated a temperature of about 300F.upon emerging from the outlets of said flues.

By applicants invention about 86% of all the heat available in the gasis utilized.

The heated circulating medium may be e1nployed for industrial hot watersupply, auxiliary low pressure steam, house heating and other purposes.The openings 44 are supply tappings and the openings 45 are returntappings. The openings 44 and 45 at either side of the boiler may beconnected to the circulating heatin system for supplying heating I HI:

fluid to radiators or other heat emitting apparatus. The openings 44 and45 not in use may be sealed with suitable closures 46.

I have found, for example, that satisfactory results may be obtained bya construction in which said hollow section may be approximately 20inches wide, 30 inches high and 3 inches thick. In the assembled boilerof that size the distance between the central portions of the opposingwalls of each flue is 1 inch. The transverse flue area at the bottom ofeach flue just above the burner is about 30 square inches. the topof-each flue on a line with the center of the upper nipple part is 13.5square The corresponding area at inches. The corresponding flue areabetween two opposing rows of projections averages 16.5 square inches.The height of each projection 36 is 0.4375 inches; the diameter at thebase of the projection 0.3175 inches; the average diameter of theprojection 0.2525 inches; the external or exposed surface of theprojection 0.3277 square inches; the area covered by the base of theprojection 0.0791 square inches; the distance horizontally betweenprojections (center to center) is .75 inches, and the distancevertically between the same is 1 inch. The proportionate amount of outerwall surface for each projection is a rectangle 1 inch by .75 inches. Aunit of outer wall surface, therefore, will consist of such rectan le of.75 square inches, less the area of the ase of one projection .0791 thusleaving .6709 square inches, plus .3277 square inches, the externalsurface of the projection, while a corresponding area or unit of innerwall surface will be merely a rectangle 1 inch by .75 inches equaling.75 square inches. The ratio of outer to inner surface will,

therefore be or 1.33.

Having thus described my invention what I claim and desire to secure byLetters Patent is;

1. A boiler of the character described comprising a plurality of watercontaining sections forming flues therebetween, and a plurality ofrelatively small tapering projections distributed over the opposingwalls of said flues and extending into the path of the hot gases andproducts of combustion passing therethrough, and serving to divide eachflue into a series of uninterrupted vertical passages, each of whosearea in cross-section is relatively wide at its intermediate portion andtapering towards the opposite ends thereof; and in which the ratio of arectangular area of said flue wall whose sides are tangent to theoutermost rows of projections, together with the area of its saidprojections, is about 1.33 times the area of the correspondinrectangular area of inner wall surface, su stantially as specified.

2. A boiler of the character described comprisin a plurality of watercontaining sections or'ming flues therebetween, and a plurality ofrelatively small tapering projections distributed over the opposingwalls of said flues and extending into the path of the hot gases andproducts of combustion passing therethrough and serving to divide saidflue into a series of uninterrupted vertical passages, each of whosearea in cross-section is relatively wide at its intermediate portion andtapering towards the opposite ends thereof, and in which the ratio ofthe exposed area of one of said projections and its proportionate amountof surrounding wall surface is about 1.33 times the area of acorresponding unit of inner wall surface, substantially as specified.

3. A boiler of the character described comprisin a plurality of watercontaining sections orming a relatively narrow flue therebetween, and aplurality of relatively small projections distributed over the opposinwalls of said flue in staggered relation an extending into the path ofand entirely ex posed to the hot gases and products of combustionpassing therethrough, and spaced laterally from one another a distanceslightly greater than the maximum diameter thereof to divide said flueinto a series of uninterrupted vertical passages to permit of the flowof the hot gases and products of combustion through said flue at suchvelocity to insure the maximum absorption of heat by the contents of theboiler; and in which the ratio of a unit of outer wall surface of thatpart lying within an outline coinciding substantially with the outermostof the projections extending from said flue wall together with theexposed area of said projections, ranges from 1.2 to 1.5 times the areaof a corresponding unit of inner wall surface, substantially asspecified.

4. A boiler of the character described com prising a plurality of watercontaining sections forming a relatively narrow flue therebetween forthe passage of the hot gases and products of combustion, and a pluralityof relatively small, tapering, solid projections distributed over theopposing walls of said flue and extending into the path of the hot gasesand roducts of combustion passing therethroug and serving to divide saidflue into a series of uninterrupted vertical passages each of whose areain cross-section is relatively wide at its intermediate portion andtapering towards the ends thereof and whose longer axis is disposed atright angles tp t(l11e plane of said flue, substantially as spec- 1 1e5. A boiler of the character described comprising water containingsections forming a flue therebetween,and a pluralityof relatively smallsolid projections extendi from the wall of said flue into the path ofthe hot gases and products of combustion passing therethrough; each ofsaid projections having a cross sectional area at the base thereof whichis approximately one quarter of the area of the entire exposed surfacethereof, substantially as specified.

6. A boiler of the character described comprising a plurality of watercontaining sections forming a flue therebetween, and a plurality ofrelatively small substantially solid projections extending from thewalls of said flue into the path of the hot gases and products of comustion passing therethrough; each of said projections having a lengthgreater than the average diameterthereofand less than twice saiddiameter, and havin a cross sectional area at the base thereof which isapproximately one quarter of the area of the entire exposed surfacethereof, substantially as specified.

7. A boiler of the character described comprising a plurality of watercontaining sections forming a flue therebetween, and a plurality of rowsof relatively small projections extending from the wall of said flueinto the path of the hot gases and products of-comb-ustion passingtherethrough; the projections of ments forming a flue therebetween, anda plurality of rows of relatively small solid proj ections extendingfrom the walls of said flue into the path of the hot gases and productsof combustion passing therethrough; the projections of each row beingspaced 'from one another a distance slightly greater than the maximumdiameter thereof and being staggered relative to the projections of theadj acent rows at opposite sides thereof, substantially as specified.

9. A boiler of the character described comprising a plurality of Watercontaining sections orming a vertical flue therebetween, and a pluralityof horizontal, parallel rows of relatively small solid projectionsextending from the opposing walls of said flue into the path of the hotgases and products of combustion passing therethrough; said projectionseach having a length greater than the average diameter thereof and lessthan twice said diameter; and the projections of each row being spacedfrom one another a distance slightly exceeding the maximum diameterthereof, and bein staggered relative tothe projections of t e adjacentrows at opposite sides thereof and being arranged to form a series ofvertical flues whose area in cross-section is relatively Wide at itsintermediate portion and tapering towards its opposite ends,substantially as specified.

10. A boiler of the character described comprising a plurality of watercontaining elements forming a flue therebetween, and a plurality of rowsof relatively small solid projections extending from the opposing wallsof said flue into the path of the hot gases and products of combustionpassing therethrough; the projections of each row being arranged inalinement with and in spaced relation to the corresponding projectionsof the opposing row, and being spaced from one another a distanceslightly exceeding the maximum diameter thereof, and being staggeredrelative to the projections of the adjacent rows at opposite sidesthereof; each of said projections having a length greater than theaverage diameter thereof and lessthan twice said diameter, and having across sectional area at the base thereof which is approximately onequarter of the area of the entire exposed surface thereof, substantiallyas specified.

Signed at the city of New York, inthe county and State of New York, thistwentyeighth day of September, one thousand nine hundred andtwenty-five.

EDWARD R. DOWNE.

